For years, astronomers have been unable to find up to half of the baryonic matter in the universe. We may just have solved this problem.

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We’ve known for some time that around 95% of the energy content of the universe is in dark matter and dark energy. This dark sector doesn’t interact with light in any way and so is invisible to us. The remaining 5% - the light sector – represents all of the regular matter in the universe. Yet what if I told you that all of the stars and galaxies and galaxy clusters only comprise 10% of the light sector. The rest has proved as elusive as the dark sector. We think it must exist as extremely diffuse gas in between the galaxies, yet our intense searches miss up to half of it. At least until now.